Stability of total phenolic concentration and antioxidant capacity of extracts from pomegranate co-products subjected to in vitro digestion.
BMC Complement Altern Med
; 16: 358, 2016 Sep 13.
Article
en En
| MEDLINE
| ID: mdl-27618992
BACKGROUND: Co-products obtained from pomegranate juice processing contain high levels of polyphenols with potential high added values. From value-addition viewpoint, the aim of this study was to evaluate the stability of polyphenolic concentrations in pomegranate fruit co-products in different solvent extracts and assess the effect on the total antioxidant capacity using the FRAP, DPPHË and ABTS(+) assays during simulated in vitro digestion. METHODS: Pomegranate juice, marc and peel were extracted in water, 50 % ethanol (50%EtOH) and absolute ethanol (100%EtOH) and analysed for total phenolic concentration (TPC), total flavonoids concentration (TFC) and total antioxidant capacity in DPPHË, ABTS(+) and FRAP assays before and after in vitro digestion. RESULTS: Total phenolic concentration (TPC) and total flavonoid concentration (TFC) were in the order of peel > marc > juice throughout the in vitro digestion irrespective of the extraction solvents used. However, 50 % ethanol extracted 1.1 to 12-fold more polyphenols than water and ethanol solvents depending on co-products. TPC and TFC increased significantly in gastric digests. In contrast, after the duodenal phase of in vitro digestion, polyphenolic concentrations decreased significantly (p < 0.05) compared to those obtained in gastric digests. Undigested samples and gastric digests showed strong and positive relationships between polyphenols and the antioxidant activities measured in DPPH, ABTS(+) and FRAP assays, with correlation coefficients (r (2)) ranging between 0.930-0.990. In addition, the relationships between polyphenols (TPC and TFC) and radical cation scavenging activity in ABTS(+) were moderately positive in duodenal digests. CONCLUSION: Findings from this study showed that concentration of pomegranate polyphenols and the antioxidant capacity during in vitro gastro-intestinal digestion may not reflect the pre-digested phenolic concentration. Thus, this study highlights the need to provide biologically relevant information on antioxidants by providing data reflecting their stability and activity after in vitro digestion.
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Bases de datos:
MEDLINE
Asunto principal:
Fenoles
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Extractos Vegetales
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Depuradores de Radicales Libres
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Lythraceae
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Modelos Biológicos
Tipo de estudio:
Prognostic_studies
Idioma:
En
Revista:
BMC Complement Altern Med
Año:
2016
Tipo del documento:
Article
País de afiliación:
Sudáfrica